Fórum Subcomponente em um CollectionItem #417611

unit MX.DataSetsAbstract;

interface

uses
  Data.DB, System.Classes, System.SysUtils, Datasnap.DBClient;

type
  TDSItem = class;
  TDSCollection = class;

  TDSItem = class(TCollectionItem)
  private
    FDataSet: TClientDataSet;
    procedure SetDataSet(const Value: TClientDataSet);
    function GetDataSet: TClientDataSet;
  protected
    function GetDisplayName: String; override;
  public
    constructor Create(Collection: TCollection); override;
    destructor Destroy; override;
  published
    property DataSet: TClientDataSet read FDataSet write SetDataSet;
  end;

  TDSCollection = class(TCollection)
  private
    FOwner: TPersistent;
    function GetItems(Index: Integer): TDSItem;
  protected
    function GetOwner: TPersistent; override;
  public
    constructor Create(Owner: TComponent);
    function Add: TDSItem;
    function Insert(Index: Integer): TDSItem;
    property Items[Index: Integer]: TDSItem read GetItems;
  end;

implementation

{$Region ( TCustomItem ) }

constructor TDSItem.Create(Collection: TCollection);
begin
  inherited Create(Collection);
  FDataSet := TClientDataSet.Create(SELF);  // SELF NÃO FUNCIONA POIS NÃO É TCOMPONENT, E SIM TPERSISTENT
  FDataSet.Name := ClientDataSet;
end;

destructor TDSItem.Destroy;
begin
  FDataSet.Destroy;
  inherited;
end;

function TDSItem.GetDataSet: TClientDataSet;
begin
  Result := FDataSet
end;

function TDSItem.GetDisplayName;
begin
  inherited;
  Result := Format(Item %d, [Index]);
end;

procedure TDSItem.SetDataSet(const Value: TClientDataSet);
begin
  FDataSet := Value;
end;

{$EndRegion}

{$Region( TCustomCollection )}

function TDSCollection.Add: TDSItem;
begin
  Result := TDSItem(inherited Add);
  Result.FDataSet := TClientDataSet.Create(NIL);
  Result.FDataSet.Name := DataSet + IntToStr(Result.Index);
end;

constructor TDSCollection.Create(Owner: TComponent);
begin
  inherited Create(TDSItem);
  FOwner := Owner;
end;

function TDSCollection.GetItems(Index: Integer): TDSItem;
begin
  Result := TDSItem(inherited Items[Index]);
end;

function TDSCollection.GetOwner: TPersistent;
begin
  Result := FOwner;
end;

function TDSCollection.Insert(Index: Integer): TDSItem;
begin
  Result := TDSItem(inherited Insert(Index));
end;

{$EndRegion}

end.